Winston Peters says Andrew Little should no longer be referred to as "leader of the Opposition" after Labour's leaked internal polling showed a dramatic drop in support for the party.
The results show Labour is on 26 percent support, crashing from 34 percent in May, while NZ First has risen 5 percent to 14 percent, overtaking the Greens who are on 13 percent.
Speaking to The Nation on Saturday, Mr Peters said with this kind of polling, Mr Little won't be getting into Parliament.
"If you go from 26 down to 22, that's it. Andrew is not in Parliament. So why would you make these statements, that he's the next leader of the country? Or the leader of the Opposition?"
Mr Little isn't contesting an electorate this election, so Labour runs the risk of filling its party vote quota with electorate MPs - shutting the leader out.
Asked if he could potentially be Prime Minister leading Labour and the Greens - who Mr Peters has previously referred to as "extremists" - if Labour doesn't poll well at the election, Mr Peters said he wouldn't be "counting his chickens before they hatch".
"We are totally focused on the 23rd of September and not the day after.
"Out there, there are millions of people now who need NZ First to do dramatically well in this election to see an economic change - a real one. Not the economy that Greens and Labour and the National Party all accept."
Labour and UMR said the poll results had not yet been released to Labour, and the leak must have come from a corporate client who had already been provided the results.